1. Field of the Invention
The present invention relates to a new and improved apparatus for reburning ash material of a previously burned primary fuel. More particularly, the reburning apparatus is especially adapted for use in a parallel combustion path with a primary combustion unit such as that used in the lumbering industry where the primary fuel is waste wood products. Burning of waste wood products generally produces a relatively high percentage or volume of ash material and, a portion of this ash material is usually not completely combusted leaving unburned carbon and other unoxidized constituents which can provide additional heat energy if burned efficiently. Because of the high volume of ash material produced in the primary combustion process it is desirable to further oxidize or reburn the ash material available from the primary combustion unit so that the amount of total boiler ash is minimized and thus available landfill capacity for the boiler ash is not overburdened with excessive volume.
2. Background of the Prior Art
Previous attempts to more efficiently burn available fuel such as waste wood products so that all of the carbon content is efficiently oxidized and a lower volume of ash material is obtained have not met with great success because of a number of factors such as highly variable flow rates, relatively little transit time to obtain more complete combustion and disruption of the fuel burning process in a primary combustion unit when attempts at reinjecting burned ash material into the process have been utilized.
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